Automotive transmissions are normally installed in trucks and automobiles by mounting them on a cross-arm attached to the frame of the vehicle. A transmission mount, normally consisting of two horizontal metal plates attached together via a rubber-filled core, is inserted between the bottom of the transmission housing and the top of the cross-arm to provide support and shock-absorption for the transmission. In most vehicles the top plate of the mount is secured to the bottom of the transmission's housing by means of two perforations properly spaced apart and sized to receive corresponding studs or bolts protruding down from the transmission. Similarly, the bottom plate of the mount features one, two, or three studs or threaded holes designed to match corresponding apertures or bolts, respectively, in the top of the cross-arm.
Thus, the mount is first fastened to the top of the cross-arm by securing its bottom plate thereto; the transmission is then installed on top of the mount and secured to the top plate thereof, as well as to other parts of the vehicle and of the drive-train. Once so assembled, the transmission is firmly braced to and supported by the cross-arm through the rubber mount so installed, which also provides shock absorption to alleviate the effects of vibration during the operation of the vehicle.
One example of such a contemporary automotive transmission mount is disclosed in U.S. Pat. No. 5,251,865, issued to Kelly on Oct. 12, 1993. The Kelly patent discloses a transmission mount having a rubber core disposed intermediate a top plate configured for attachment to the transmission housing and a bottom plate configured for attachment to the supporting cross-arm of the vehicle frame.
Although such contemporary automotive transmission mounts have proven generally suitable for their intended purposes, they possess inherent deficiencies which detract from their overall effectiveness in the marketplace. One example of such an inherent deficiency is readily apparent in the Kelly device, wherein the upper and lower plates thereof do not interlock. Thus, deterioration and/or debonding of the resilient material disposed therebetween can result in complete detachment of the upper plate from the lower plate, thereby rendering the Kelly automotive transmission mount ineffective.
Additionally, the Kelly automotive transmission mount, as is typical of contemporary automotive transmission mounts, utilizes rubber as the resilient material thereof. As is well known to those skilled in the art, rubber is susceptible to degradation due to various environmental factors, such as contamination by various automotive fluids, e.g., gasoline, oil, transmission fluid, brake fluid, etc., as well as ozone and other atmospheric pollutants.
As such, although the prior art has recognized to a limited extent the problem of bracing and supporting automotive transmissions to the frame cross-arm of a vehicle, the proposed solutions have, to date, been ineffective in providing a satisfactory remedy.